Reel capable of winding tape without side stairs and tape drive having the reel

ABSTRACT

A reel for winding a magnetic recording tape used to record/reproduce information or data. The reel comprises a hub and a pair of flanges extending from axial ends of the hub in a direction perpendicular to an axis of the hub. The hub has a taper in shape such that the outer diameter of the hub is gradually reduced form an axial end to the other axial end thereof.

BACKGROUND OF THE INVENTION

[0001] This invention relates to a magnetic recording tape drive (tapedrive) for driving a magnetic recording tape (tape) contained in a tapecartridge for recording/reproducing data or information to/from the tapeand, in particular, to a reel, adopted to such a magnetic tape drive,for winding the tape thereon.

[0002] As tape drives of the type, there have been known a variety oflinear tape storage drives, such as DLT (Digital Linear Tape) and LTO(Linear Tape Open). The tape drives have been developed as “backup”memories for computer systems. Such a tape drive comprises a reel calleda take-up reel and is adapted to receive loading of a tape cartridgehaving a single reel (for example, see U.S. Pat. No. 5,862,014). Whenthe tape cartridge is loaded as a supply reel in the tape drive, amagnetic tape is pulled out from the supply reel and is taken up by orwound onto the take-up reel, which is rotating at a high speed, througha magnetic head. An example of the tape cartridge is disclosed inJapanese Unexamined Patent Publication No. 149491/2000.

[0003] The reel mounted in the existing tape drive of the type comprisesa central cylindrical shaft, a central ring, or a hub and a pair offlanges extending from opposite axial ends of the hub in a directionperpendicular to an axis of the hub. The tape is wound around and on thehub and between the two flanges. The hub has an axial length extendingbetween opposite inner surfaces of the two flanges. The axial length isusually made slightly larger in size than the width of the tape wound onthe reel. The hub also has an outer diameter constant over its axiallength.

[0004] When the tape is taken up or wound onto the existing reel, a rollof the tape wound is apt to have irregularities or stairs in its sidesurface due to the difference in size between the axial length of thehub and the tape width, which will be referred to as side irregularitiesor side stairs.

[0005] When the tape is wound on the reel with the side irregularitiesor stairs, the tape running to the take-up reel deviates in a directionperpendicular to the running direction, that is, in a direction of awidth of the tape, so that a recording track of the tape is deviatedfrom a magnetic head in the width direction of the tape. This deviationof the tape may cause a problem that data are not correctly recorded orreproduced in or from the tape.

[0006] In the tape cartridge, if a tape is wound on a reel in thecartridge with the side irregularities or stairs, the similar problem iscaused because the tape taken out from the cartridge deviates in thetape width direction due to the side irregularities.

SUMMARY OF THE INVENTION

[0007] It is therefore an object of the present invention to provide areel capable of winding a tape without side irregularities or stairs onthe reel.

[0008] Further, it is another object of this invention to provide a tapedrive having the reel capable of winding a tape without sideirregularities or stairs on the reel.

[0009] The other objects, features, and advantages of the presentinvention will become clear as the following description proceeds.

[0010] According to an aspect of the present invention, there isprovided a reel for winding a magnetic recording tape used torecord/reproduce information or data. The reel comprises a hub forwinding the magnetic recording tape thereon and a pair of flangesextending from axial ends of the hub in a direction perpendicular to anaxis of the hub. The hub has a taper such that it has an outer diametergradually reduced in size along the axis from a first one to the othersecond one of the axial ends.

[0011] In the reel, the pair of flanges are provided with inner surfacesfaced to each other, and one of said pair of flanges extending from saidfirst axial end of said hub is finished flat substantially without warpand roughness.

[0012] According to another aspect of the present invention, there isprovided a magnetic recording tape drive for drive the magneticrecording tape. The drive comprises a reel. The reel comprises a hub forwinding the magnetic recording tape thereon and a pair of flangesextending from axial ends of the hub in a direction perpendicular to anaxis of the hub. The hub has a taper such that it has an outer diametergradually reduced in size along the axis from a first one to the othersecond one of the axial ends.

[0013] In an embodiment of the magnetic recording tape drive, the reelis arranged in a tape drive with an orientation so that the hub extendsin the vertical direction with the first axial end being positionedupper than the second axial end.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014]FIGS. 1A and 1B are a top plan view and a sectional view,respectively, showing an existing reel with tape wound;

[0015]FIGS. 2A and 2B are a top plan view and a sectional view,respectively, showing a reel with a tape wound according to anembodiment of the present invention, providing that the reel is mountedin a tape drive with an orientation shown by an arrow;

[0016]FIGS. 3A and 3B are a top plan view and a sectional view,respectively, showing the reel with a tape wound, providing that thereel is reversely mounted up and down with respect to the orientation inFIGS. 3A and 3B; and

[0017]FIG. 4 is a perspective view showing a tape drive having the reelof FIGS. 2A and 2B mounted therein.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0018] In order to facilitate an understanding of the present invention,description will at first be made about the existing reel mounted in theexisting tape drive with reference to the drawing.

[0019] Referring to FIGS. 1A and 1B, an example of the existing reel 30is provided with a hub 31 having a cylindrical shape and a pair offlanges 32 formed on axial ends of the hub 31. The hub 31 is straight,in other words, the hub 31 has an outer diameter constant along theaxial direction. The flanges 32 extend from the axial ends of the hub ina direction perpendicular to the axis of the hub 31. Each of the flanges32 is formed in a general rectangular shape as shown in FIG. 1A, but canbe made in a disk shape or any other shape as is desired.

[0020] A tape 33 is wound around the hub 31 and between the flanges 32to form a tape roll. Side surfaces of the tape roll are not always madesmooth and flat, but often or rather always made in an irregular surfacewith side stairs 33 a. This is because the axial length of the hub 31and a distance left between the two flanges 32 are set slightly largerin size than a width of the tape 33. The side irregularities or sidestairs 33 a of the wound tape roll have a problem as described in thepreamble of the description.

[0021] If the axial length of the hub 31 and the distance between theflanges 32 would be made equal to the width of the tape, the sideirregularities or stairs are removed but there occurs another problemthat side edges of the tape 33 engage and collide to the flanges 32 andare thereby worn and/or damaged.

[0022] Now, preferred embodiment of the present invention will bedescribed with reference to the drawing.

[0023] Referring to FIGS. 2A and 2B, a reel 10 according to anembodiment of this invention is similar to the existing art shown inFIGS. 1A and 1B, and is used for winding a magnetic recording tape usedto record/reproduce information or data and installed in a magneticrecording tape drive as shown in FIG. 4. The reel 10 is different fromthe existing reel 30 shown in FIGS. 1 and 2 in that a hub 11 having acylindrical shape is not straight as the hub 31 of the existing reel 30shown in FIGS. 1A and 1B, but is formed in a tapered shape where theouter diameter of the hub 11 gradually reduces from an axial end to theother axial end. Thus, the hub 11 has a large-diameter axial end 11a anda small-diameter axial end 11 b.

[0024] A distance left between inner surfaces 321 of the flanges 32 isalso designed slightly larger in size than the width of the tape 33,which is similar to that in the existing reel shown in FIGS. 1A and 1B.

[0025] In FIGS. 2A and 2B, the reel 10 is arranged in the tape driveshown in FIG. 4 so that the axis of the hub 11 extends in a verticaldirection while the small-diameter end 11 b is upper than thelarge-diameter end 11 a.

[0026] When the tape 33 is taken up and wound on the reel 10, side edgesof the tape 33do neither engage nor collide the flanges 32, and the tape33 is wound on the hub to gradually close to the inner surface of thelower one of the flanges 32 a that extends from the large-diameter end11 a of the hub 11. This can be understood from a fact that the tapetension is larger in a side edge portion of the tape 33 wound on thevicinity of the large-diameter end 11 a of the hub 11 than in theopposite side edge portion of the tape 33 wound on the vicinity of thesmall-diameter end 11 b of the hub 11.

[0027] Thus, the tape 33 is wound so that the lower side edge of thetape 33 is corrected to close to the inner surface of the lower flange32 a. Accordingly, the tape 33 can be wound into a roll without the sideirregularities and/or side stairs. In the state wound, the upper sidesurface of a roll of the tape 33 wound can resultantly be flat and faceto the inner surface of the upper flange 32 b, which extends from thesmall-diameter end 11 b of the hub 11, with a clearance a lefttherebetween.

[0028] As the lower flange 32 a engages the side edge of the tape 33,the inner surface of the lower flange 32 a preferably be finished smoothand flat substantially without any warp and/or roughness.

[0029] Next, the reel 10 can be made to reversely be set up and down inthe tape drive.

[0030] Referring to FIGS. 3A and 3B, the reel 10 is arranged in the tapedrive shown in FIG. 4 so that the large-diameter end 11 a of the hub 11is upper than the small-diameter 11 b of the hub 11.

[0031] In the setting condition of the reel 10, when the tape 33 iswound on the reel 10, the tape is gradually close to the inner surfaceof the upper flange 32 a which extends from the large-diameter end 11 aof the hub 11, in the similar manner as in the condition shown in FIGS.2A and 2B. Therefore, the tape 33 is wound in a roll of the tape 33 witha flat side surfaces without side irregularities and/or side stairs. Itwill be under stood that there is formed a clearance c between theunderside of the roll of the tape 33 and the inner side of the lowerflange 32 b.

[0032] When the tape 33 is further wound into the reel 10 and increasesthe diameter of the roll of the tape 33 wound, the weight of the taperoll cannot be ignored. An outer portion of the tape roll graduallydescends so that the clearance c between the underside of the roll andthe inside of the lower flange 32 b is gradually reduced while aclearance b is gradually generated and increased between the upper sideof the roll and the inside of the upper flange 32 a. Consequently, thelower edge of the tape 33 is not touched to the inner surface 321 of theupper flange 32 a. Thus, the tape 33 becomes more smoothly wound on thereel 10, because no friction resistance occurs between the flanges 32and the tape 33.

[0033] Thus, the roll of the tape 33 wound has smooth side surfaceswithout side irregularities and/or side stairs.

[0034] In FIGS. 2A to 3B, the hub 11 has the outer diameter that islinearly changed, but it may be hanged non-linearly as long as thediameter reduces from one end to the other end of the hub.

[0035] It is preferable that flanges of the reel is made from a materiallow in friction coefficient.

[0036] Next, a DLT as an example of a magnetic recording tape driveusing the reel 10 shown in FIGS. 2A to 3B will be described withreference to the drawing.

[0037] Referring to FIG. 4, the tape drive 50 of the DLT is adapted toremovably receive a tape cartridge (not shown) having a magnetic tape.The tape drive 50 includes a take-up reel 20 in the interior thereof.The reel 10 shown in FIGS. 2A-3B is used as the take-up reel 20, in thesetting condition shown in FIGS. 2A and 2b or in FIGS. 3A and 3B.

[0038] The tape drive 50 comprises a substantially rectangular housing52 having a common base 52 a. The housing 52 comprises a sheet metalchassis made of an iron-based magnetic material. The base 52 a has firstand second spindle motors 53 and 54.

[0039] The first spindle motor 53 is connected to the reel 20 mounted tothe base 52 a. The reel 20 is dimensioned to accept a magnetic tape (notshown) streaming at a relatively high speed. The first spindle motor 53may be called a take-up reel motor. The second spindle motor 54 isadapted to drive the tape cartridge. The second spindle motor 54 may becalled a supply reel motor.

[0040] The tape cartridge is manually or automatically inserted in thetape drive 50 via a slot 52 b formed on the housing 52 of the drive 50along an inserting direction depicted by an arrow A. When the tapecartridge is inserted in the tape drive 50, the tape cartridge isengaged with the second spindle motor 54 by a loading mechanism (notshown). Prior to rotation of the first and the second spindle motors 53and 54, the magnetic tape is connected to the reel 10 mounted as thetake-up reel 20 or a leader tape pulled out therefrom. When the firstand the second spindle motors 53 and 54 are driven, the magnetic tapemoves at a high speed and guided to a position between the flanges 32 ofthe reel 10 to be taken up on the hub 11. A plurality of guide rollers56 defines a tape path between the tape cartridge and the reel 10 andguide the magnetic tape as it streams at a relatively high speed.

[0041] The tape drive 50 further comprises a head assembly 60 having amagnetic head for recording and reproducing data to and from themagnetic tape. The head assembly 60 is positioned to face the tape pathdefined by the guide rollers 56. During operation of the tape drive 50,the magnetic tape streams on the tape path, coming into close proximityto the head assembly 60 while streaming along the tape path. Thus, dataexchange between the magnetic tape and the magnetic path is enabled.

[0042] While the present invention has thus far been described inconjunction with the embodiments thereof, it will readily be possiblefor those skilled in the art to put the present invention into practicein various other manners.

What is claimed is:
 1. A reel for winding a magnetic recording tape used to record/reproduce information or data, said reel comprising: a hub for winding the magnetic recording tape thereon and, said hub having first and second axial ends and having a taper in shape such that said hub has an outer diameter gradually reduced in size along the axis from the first axial end to the second axial end; and a pair of flanges extending from first and second axial ends of the hub, respectively, in a direction perpendicular to an axis of said hub.
 2. The reel according to claim 1, wherein said pair of flanges are provided with inner surfaces faced to each other, and first one of said pair of flanges extending from said first axial end of said hub is finished flat substantially without warp and roughness.
 3. A magnetic recording tape drive for drive the magnetic recording tape, said drive comprising a reel, said comprising: a hub for winding the magnetic recording tape thereon and, said hub having first and second axial ends and having a taper in shape such that said hub has an outer diameter gradually reduced in size along the axis from the first axial end to the second axial end; and a pair of flanges extending from first and second axial ends of the hub, respectively, in a direction perpendicular to an axis of said hub.
 4. The magnetic recording tape drive according to claim 3, wherein said reel is arranged in the tape drive with an orientation so that said hub extends in the vertical direction with the first axial end being positioned upper than the second axial end.
 5. The magnetic recording tape drive according to claim 3, wherein said reel is arranged in the tape drive with an orientation so that said hub extends in the vertical direction with the second axial end being positioned upper than the first axial end. 